Studies On The Design And Synthesis Of Second Structure Driven By CH…O Hydrogen Bond In Crystal Growth

The rational design and construction of molecular aggregates possessing multi-level structure is an important frontier research in chemistry. And how to accurately design and utilize intermolecular weak interaction forces to obtain particular molecular assemble system with high-level structures is a research item full of challenge, because the diversity of molecular structure could cause multiple molecular stacking models during the course of crystal growth. So it is difficult to predict molecular stacking model based on a single molecular structure. Obviously, if a series of assemble units with multiple substituted groups show the same assemble area in the self-assemble course, and conveys anticipated base assemble model, we can use it to synthesize molecular aggregation with anticipated stacking models, which provides a foundation of building theory and guidance for high-level structure's rational design and synthesis.In this thesis, the research works on weak CH...O hydrogen bond in solid phase was systematically reviewed. We used a series of molecular clips based on glycoluril having various substituted groups as research objects, and studied the rule of formation of secondary structure using weak CH...O hydrogen bond as main driven forces. The research results were summarized below:Thirteen symmetrical and asymmetrical molecular clips based on diethoxycarbonyl glycoluril with different substituted groups of aromatic rings (H, OMe, NO₂, Me, Br) were designed and synthesized, and crystal structures of twelve compounds were obtained. We firstly attained a system that various structures can assemble the same secondary structure using weak CH...O hydrogen bond as main driven forces, in which p-dimethoxy-o-xylylene rings are in the interior of the dimeric molecular clips. Then it will provide much great enlightenment and reference meaning for the rational design and synthesis of more high-level structures.Furthermore, in order to investigate the high-level structure formation rule of molecular clips constructed by glycoluril with different substituted groups during crystal growth, eleven kinds of glycoluril compounds and nine molecular clips based on these glycoluril compounds were synthesized, and crystal structure of five molecular clips were also obtained. After analysis of these crystal structures, it can conclude that various structure of substituted group can cause variety of stacking models. Such as high-level structure of compound III-2a (R = H) can be obtained, but this high-level structure will disappear when H atom is displaced by other groups, these substituted groups destroyed this assemble model. We also described the function of solvent molecule in polymorphs about crystal packing.Besides, synthesis of novel artificial acceptors is also a hotspot of supramolecular chemistry. The major intermediate compound FV-1 was synthesized firstly using one-pot method with cheap diphenylglycoluril as building block. The advantage of this method is mild condition, single product formation, good yield, and no need for separating intermediates. Meantime, synthesis exploration of steric macrocyclic compound was also proceeded, which provided experiment foundation for gaining synthesis method of a novel kind of artificial acceptor. And 6 crystal structure of molecular clips based on diphenylglycoluril were also obtained, and formation rule of high-level structure during crystal growth was conferred. It is especially taking care that the assemble model of racemic dimmers with center symmetry can be obtained in crystal structure of enantiomers IV-(±)8 and IV-(±)11, which is also a kind of selective assemble model driven by weak CH... O hydrogen bond.